"One could imagine a very ascetic sort of life ... where the body is ignored. This is something I've played with in my books, where people hate to be reminded sometimes that they have bodies, they find it very slow and tedious."
- William Gibson

The notion of a separate world, or plane of existence, or realm, has existed in the human imagination from time immemorial. The classical Greeks used the ideas of Mount Olympus and Hades' underworld as different realms that existed along with our own; the ancient Hindus used the idea of a multiplicity of realms called "lokas".